The Colt Defense LE901 is field convertible carbine. The operator, without specialized tools can configure the weapon from a short barreled 5.56 x 45 CQB platform to a full sized rifle in 7.62 x 51 NATO for precision fire support. In addition to caliber changes, the operator may elect to switch from a direct gas impingement operating system to a piston driven or hybrid arrangement. The key to Colt’s flexibility is the Universal Lower Receiver or ULR.

The ULR permits the individual user – with no special tools – to convert a “single serialized lower receiver” into multiple caliber, barrel-length, and operating system configurations.